Exodus 15:22-26

22. Then Moses led Israel from the Red Sea and they went into the Desert of Shur. For three days they traveled in the desert without finding water.
23. When they came to Marah, they could not drink its water because it was bitter. (That is why the place is called Marah. )
24. So the people grumbled against Moses, saying, "What are we to drink?"
25. Then Moses cried out to the LORD, and the LORD showed him a piece of wood. He threw it into the water, and the water became sweet. There the LORD made a decree and a law for them, and there he tested them.
26. He said, "If you listen carefully to the voice of the LORD your God and do what is right in his eyes, if you pay attention to his commands and keep all his decrees, I will not bring on you any of the diseases I brought on the Egyptians, for I am the LORD, who heals you."

Numbers 21:4-9

4. They traveled from Mount Hor along the route to the Red Sea, to go around Edom. But the people grew impatient on the way;
5. they spoke against God and against Moses, and said, "Why have you brought us up out of Egypt to die in the desert? There is no bread! There is no water! And we detest this miserable food!"
6. Then the LORD sent venomous snakes among them; they bit the people and many Israelites died.
7. The people came to Moses and said, "We sinned when we spoke against the LORD and against you. Pray that the LORD will take the snakes away from us." So Moses prayed for the people.
8. The LORD said to Moses, "Make a snake and put it up on a pole; anyone who is bitten can look at it and live."
9. So Moses made a bronze snake and put it up on a pole. Then when anyone was bitten by a snake and looked at the bronze snake, he lived.

James 5:13-16

13. Is any one of you in trouble? He should pray. Is anyone happy? Let him sing songs of praise.
14. Is any one of you sick? He should call the elders of the church to pray over him and anoint him with oil in the name of the Lord.
15. And the prayer offered in faith will make the sick person well; the Lord will raise him up. If he has sinned, he will be forgiven.
16. Therefore confess your sins to each other and pray for each other so that you may be healed. The prayer of a righteous man is powerful and effective.